Jay Moreland wrote:

I need to find out if there is an official maximum amount of precession
for a Directional Gyro. My aircraft precesses 10 degrees in 10 minutes
during mostly straight and level flight with only a few shallow banks.

One avionics tech told me that it depends on the gyro manufacturer as to
what is acceptable. He also told me that an out of the box unit tested
on the table should not precess more than ONE degree in four minutes.

Jay Moreland

Its too much. I had a new gyro that precessed about 3 degrees in 15, even
though the installer told me it would be better than that. I marked it
up to salesmanship. Later, the gyro developed a problem because of
manufacturing defect that was covered by the maker. Maker gets the gyro,
and pronounces its precession out of range. I told them then it had
allways been out of range, I had no way to know it should have been
better. They told me to pound salt, since the product was out
of warranty. I had it fixed by a third party shop, now it gets less
than 1 degree per 15 or less -- basically inperceptable.

By the way, it was Century, and they can pound salt the next time I buy
avionics of any kind. Their customer support policy sucks, and the
person there dealing with me was nasty about it as well. Besides, their
quality control is obviously suspect, since they let the unit go with
out of tolerance precession in the first place.

--
For most men, true happiness can only be achieved with a woman.
Also for most men, true happiness can only be achieved without a woman.
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